Zoekresultaten

A challenge based learning community for hydrogen development and application

Power-to-ammonia: rethinking the role of ammonia – from a value product to a flexible energy carrier (FlexNH3)

This report focuses on the feasibility of the power-to-ammonia concept. Power-to-ammonia uses produced excess renewable electricity to electrolyze water, and then to react the obtained hydrogen with nitrogen, which is obtained through air separation, to produce ammonia. This process may be used as a “balancing load” to consume excess electricity on the grid and maintain grid stability. The product, ammonia, plays the role of a chemical storage option for excess renewable energy. This excess energy in the form of ammonia can be stored for long periods of time using mature technologies and an existing global infrastructure, and can further be used either as a fuel or a chemical commodity. Ammonia has a higher energy density than hydrogen; it is easier to store and transport than hydrogen, and it is much easier to liquefy than methane, and offers an energy chain with low carbon emissions.The objective of this study is to analyze technical, institutional and economic aspects of power-to-ammonia and the usage of ammonia as a flexible energy carrier.

ACHALLENGEBASEDLEARNINGCOMMUNITYFORHYDROGEN DEVELOPMENT ANDAPPLICATION

TheUniversity of Twente, SaxionUniversityofAppliedSciences, ROCofTwente(vocationaleducation), centre of expertise TechYourFuture and the H2Hub Twente, in which various regional hydrogen interested corporations are involved, work together to shape a learning community (LC) for the development of innovative hydrogen technology. The cooperation between company employees, researchers and students provides a means to jointly work on solutions for real-life problems within the energy transition. This involves a cross-chain collaboration of technical programs, professorships and (field) experts, supported by human capital specialists. In the LC, a decentralized hydrogen production unit with storage of green hydrogen is designed and built. The main question for this research is: how can the design and construction process of an alkaline electrolyzer be arranged in a challenge based LC in which students, company employees (specialists) and researchers from the three educational institutions can learn, innovate, build-up knowledge and benefit? In this project the concept of a LC is developed and implemented in collaboration with companies and knowledge institutions at different levels. The concrete steps are described below: 1. Joint session between Human Resource and Development (HRD) specialists and engineers/researchers to explore the important factors for a LC. The results of this session will be incorporated into a blueprint for the LC by the human capital specialists. 2. The project is carried out according to the agreements of the blueprint. The blueprint is continuously updated based on the periodic reflections and observed points for improvement. 3. Impact interviews and periodic reflection review the proceeding of the LC in this engineering process. The first impact interview reveals that the concept of the LC is very beneficial for companies. It increases overall knowledge on hydrogen systems, promotes cooperation and connection with other companies and aids to their market proposition as well. Students get the opportunity to work in close contact with multiple company professionals and build up a network of their own. Also the cooperation with students from different disciplines broadens their view as a professional, something which is difficult to achieve in a mono-disciplinary project.

Power to methane.

Wind and solar power generation will continue to grow in the energy supply of the future, but its inherent variability (intermittency) requires appropriate energy systems for storing and using power. Storage of possibly temporary excess of power as methane from hydrogen gas and carbon dioxide is a promising option. With electrolysis hydrogen gas can be generated from (renewable) power. The combination of such hydrogen with carbon dioxide results in the energy carrier methane that can be handled well and may may serve as carbon feedstock of the future. Biogas from biomass delivers both methane and carbon dioxide. Anaerobic microorganisms can make additional methane from hydrogen and carbon dioxide in a biomethanation process that compares favourably with its chemical counterpart. Biomethanation for renewable power storage and use makes appropriate use of the existing infrastructure and knowledge base for natural gas. Addition of hydrogen to a dedicated biogas reactor after fermentation optimizes the biomethanation conditions and gives maximum flexibility. The low water solubility of hydrogen gas limits the methane production rate. The use of hollow fibers, nano-bubbles or better-tailored methane-forming microorganisms may overcome this bottleneck. Analyses of patent applications on biomethanation suggest a lot of freedom to operate. Assessment of biomethanation for economic feasibility and environmental value is extremely challenging and will require future data and experiences. Currently biomethanation is not yet economically feasible, but this may be different in the energy systems of the near future.

Modelling and Control of a Grid-Connected RES-Hydrogen Hybrid Microgrid

This paper proposes a Hybrid Microgrid (HμG) model including distributed generation (DG) and a hydrogen-based storage system, controlled through a tailored control strategy. The HμG is composed of three DG units, two of them supplied by solar and wind sources, and the latter one based on the exploitation of theProton Exchange Membrane (PEM) technology. Furthermore, the system includes an alkaline electrolyser, which is used as a responsive load to balance the excess of Variable Renewable Energy Sources (VRES) production, and to produce the hydrogen that will be stored into the hydrogen tank and that will be used to supply the fuel cell in case of lack of generation. The main objectives of this work are to present a validated dynamic model for every component of the HμG and to provide a strategy to reduce as much as possible the power absorption from the grid by exploiting the VRES production. The alkaline electrolyser and PEM fuel cell models are validated through real measurements. The State of Charge (SoC) of the hydrogen tank is adjusted through an adaptive scheme. Furthermore, the designed supervisor power control allows reducing the power exchange and improving the system stability. Finally, a case, considering a summer load profile measured in an electrical substation of Politecnico di Torino, is presented. The results demonstrates the advantages of a hydrogen-based micro-grid, where the hydrogen is used as medium to store the energy produced by photovoltaic and wind systems, with the aim to improve the self-sufficiency of the system